Segmental resistance-board



(No Model.)

G. D. HAND 8: 0. P. SELLS. SEGMENTAL RESISTANCE BOARD.

No. 448,838. Patented Mar. 17,1891.

UNITED STATES PATENT OEEIcE.

GIDEON DAVID HAND AND OSBORN PAR-KER SELLS, OF CHICAGO, ILLINOIQ SEGMENTAL RESISTANCE-BOARD.

SPECIFICATION forming part of Letters Patent No. 448,838, dated March 17, 1891.

Application filed August- 11, 1890. Serial No. 361,658. (No model.)

To all whom it may (JOILCCI'IL:

Beit known that we, GIDEON DAVID HAND and OSBORNPARKER SELLs, both of Chicago, Cook county, Illinois, have invented certain new and useful Improvements in Segmental Resistance-Boards for Electric-Light Circuits, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

The object of our invention is to so improve the segmental resistance-bands used for regulating the glow of incandescent lights in theaters, halls, and public places, that a change from a bright to a darker light, or vice versa, can be easily and promptly made, and which, considering the number of segmental plates used, is much more compact and occupies less space than those now in use, substantially as hereinafter fully described, and as illustrated in the drawings, in which Figure l is a plan view of our invention, and Fig. 2 is a longitudinal central section therethrough.

Referring to the drawings, A represents a series of segmental contact-plates, each of which is connected by suitable wire I) to a resistance-eoil, and which are arranged in a circle upon a wooden board or plate of insulating material 13. This board is provided with a series of holes aa, one of which is located at the outer end of each plate A for the passage of the end of the resistance-coil, with which the plate in radial alignment with said holes is connected. Secured to said board 13, surrounded by and concentric with plates A, is a plate C, preferably of a circular form and having rising upon its center a pivotal stud t). Journaled upon this pivotal stud is a pinion 1), the boss of which extends downward slightly and has secured thereto the brush E. This brush has the end of its longer arm bearing down upon the inner portion of at least two of the plates A all the time, and the end of its shorter arm bears down upon the circular plate 0 at a point preferably diametrically opposite its other end. As before stated, each segment-plate A is connected to a resistance-board, the coil connected to the plate marked X having the greatest resistance, and each. plate in succession moving from left to righthaving less resistance than the one next preceding until the plate y, upon which, when said brush rests thereon, there is no resistance, as will be explained more fully hereinafter.

In order to revolve the brush 0 over the plates A in either direction, we mesh with the pinion D the segmental gear G, which is pivoted upon a stud projecting from a block ll, which is secured to board B in circular alignment with plates A. This segmental gear is oscillated by means of a handle h, projecting from the boss of said gear in a direction diametrically opposite it.

Projecting downward from the center of plate C in a direction opposite to post C is a root (Z, which has tapped into the end of it a binding-screw which at the same time serves to connect the board with the positive pole of the generator, and by means of a suitable washer keep the said root, plate, and post in position.

Each segment-plate A is provided with a binding-screw f near its outer end, so as to afford means of establishing the contact with the resistance wire or coil 1).

The segment -plate marked located at one end of the circular series of plates A, is twice the width of any other plate A, and the brush E, when the same is revolved so as to rest thereon, escapes contact with any other segment-plate.

As before stated, plate 0, post 0, and consequently the gear 1) are connected through the medium of the binding-screw c to the positive pole. From those parts the current passes through the brush E, through the segment-plates A to the resistance-coils, from whence by means of a union-wire (1 they are connected to plate 7 From plate y the circuit passes to and through the lamp system, back to the negative pole of the generator. \Vhen the brush is upon the plate y, the current passes direct therethrough through the wire g to the lamp system.

It will of course be understood that we contemplate all merely mechanical modifications of our invention as claimed herein.

What we claim as new is l. The segment-plates A, arranged in a circle, circular plate O, surrounded by and conpivotal stud projecting outward from its center and connected to the positive pole of the generator, pinion D, journaled on said stud, and brush E, secured to and moving with said pinion, in combination with a segmental gear G, and ahandle h, projecting in the opposite direction from the bossjhereof.

GIDEON DAVID HAND. OSBORN PARKER SELLS.

\Vitn esses:

CHAS. H. EVANS, FRANK D. THOMASON. 

